No abstract

The present study investigated the role of the a1-containing GABA A receptors in the neurobehavioral actions of alcohol. In Experiment 1, mice lacking the a1 subunit (a1 (À/À)) were tested for their capacity to initiate operant-lever press responding for alcohol or sucrose. Alcohol intake in the home cage was also measured. In Experiment 2, the a1 (À/À) mice were injected with a range of alcohol doses (0.875-4.0 g/kg; i.p.) to evaluate the significance of the a1 subunit in alcohol's stimulant actions. In Experiment 3, we determined if the alcohol-induced stimulant effects were regulated via dopaminergic (DA) or benzodiazepine (BDZ)-dependent mechanisms. To accomplish this, we investigated the capacity of DA (eticlopride, SCH 23390) and BDZ (flumazenil, bCCt) receptor antagonists to attenuate the alcohol-induced stimulant actions. Compared with wild-type mice (a1 ( + / + )), the null mutants showed marked reductions in both EtOH and sucrose-maintained responding, and home-cage alcohol drinking. The null mutants also showed significant increases in locomotor behaviors after injections of low-moderate alcohol doses (1.75-3.0 g/kg). bCCt, flumazenil, eticlopride, and SCH 23390 were able to attenuate the alcohol-induced stimulation in mutant mice, in the absence of intrinsic effects. These data suggest the a1 receptor plays an important role in alcohol-motivated behaviors; however, it also appears crucial in regulating the reinforcing properties associated with normal ingestive behaviors. Deleting the a1 subunit of the GABA A receptor appears to unmask alcohol's stimulatory effects; these effects appear to be regulated via an interaction of both DA-and GABA A BDZ-dependent mechanisms. Neuropsychopharmacology (2007) 32, 137-152.

Implicit outgroup favoritism has been documented in a variety of socially disadvantaged groups, yet little is known about the implications of having such bias. The present research examined whether implicit outgroup favoritism predicts judgments of ingroup versus outgroup members, and whether that relationship depends on stereotypic context. One hundred and ten African-American participants were assigned a Black versus a White work partner for a task that required skills that are stereotypically White (e.g., intellect) versus Black (e.g., athleticism). Participants rated Black partners as less competent than White partners on the stereotypically White task. Furthermore, participants who implicitly favored Whites liked Black partners less than White partners, but only on the stereotypically White task. Implications for system justification theory are discussed.

This article presents a theoretical and experimental framework for assessing the biases associated with the interpretation of numbers. This framework consists of having participants convert between different representations of quantities. These representations should include both variations in numerical labels that symbolize quantities and variations in displays in which quantity is inherent. Five experiments assessed how people convert between relative frequencies, decimals, and displays of dots that denote very low proportions (i.e., proportions below 1%). The participants demonstrated perceptual, response, and numerical transformation biases. Furthermore, the data suggest that relative frequencies and decimals are associated with different abstract representations of amount.